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arXiv · 2210.13341

Competition between energy and dynamics in memory formation

Varda F. Hagh·Chloe W. Lindeman·Chi Ian Ip·Sidney R. Nagel
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Abstract

Bi-stable objects that are pushed between states by an external field are often used as a simple model to study memory formation in disordered materials. Such systems, called hysterons, are typically treated quasistatically. Here, we generalize hysterons to explore the effect of dynamics in a simple spring system with tunable bistability and study how the system chooses a minimum. Changing the timescale of the forcing allows the system to transition between a situation where its fate is determined by following the local energy minimum to one where it is trapped in a shallow well determined by the path taken through configuration space. Oscillatory forcing can lead to transients lasting many cycles, a behavior not possible for a single quasistatic hysteron.

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Varda F. Hagh, Chloe W. Lindeman, Chi Ian Ip, Sidney R. Nagel. 2022-10-24. Competition between energy and dynamics in memory formation. https://doi.org/10.1103/physrevlett.130.197201

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